Base Path in TypeScript

Whenever working in TypeScript, we deal with importing and exporting modules in our project. This quick post is just a reminder/tutorial for how to set up a base path so that we may reference these modules in a more organized fashion.

Let's begin by creating a new project. We could just create a basic TypeScript app but let's create something a little more practical. We'll be creating a simple NextJS app that uses TypeScript. This is a pretty popular stack these days since it provides a full stack environment with the (current) most popular view library.

To start, let's navigate to a directory to make our project and run the following command.

npx create-next-app base-path-example --ts

This will build out a new Next app called base-path-example with a directory structure that looks like this:

Inside of this project, we're going to include a deeply nested path by adding a few directories inside of pages.

This is going to illustrate what happens when we have to bring in a component from way higher up in the directory tree. Here's what our deeply nested page looks like:

import { Counter } from "../../../../components/counter";

export default function CounterPage() {
  return (
    <div>
      <Counter />
    </div>
  );
}

Notice that we're bringing in this Counter component from the components directory which is four levels up. While this certainly works, it's a little difficult to read and in an app with dozens, or even hundreds of pages, these ../ pieces get annoying to deal with.

To solve this issue, we can make a quick and easy update to our tsconfig.json file which will simplify our imports throughout our entire app. Inside of tsconfig.json, add the following:

// tsconfig.json

"compilerOptions": {
  // ...
  "baseUrl": ".",
  "paths": {
      "@/*": ["./src/*"]
  }
}

This gives us a shorthand to reference the src directory. So now on any of our imports, we can just start with @. Now we can revisit that deeply nested page and make the following change:

import { Counter } from "@/components/counter";

export default function CounterPage() {
  return (
    <div>
      <Counter />
    </div>
  );
}

Now we can reference all directories and files relative to the src directory! This avoids all of the backtracking with ../! As small of a change as this may be, it will save TONS of time with imports and help your code look a lot cleaner in the process.

SIDE NOTE FOR FULL-STACK/API PROJECTS

If you are building something with ts-node or nodemon, you also need to follow this section of the ts-node docs.